"Sorry Geoff for calling you Kieth by mistake."
No prb, but Kieth is Keith:)
"I disagree with your premise that a lunar mission is less expensive than a NEO mission."
Ok.

Lunar requires delta V to land and delta V to takeoff
Nearby NEO delta V is just slightly above Lunar delta V - no landing & takeoff
Net is maybe +2 Km/sec for moon missions which means much less payload needed to LEO for the NEO mission
Less payload is less launches and less money.

Mars is less delta-v than lunar surface (if you disregard energy you can shed with aerobraking) and delta-v required to get off Mars is ignored.
Delta-v isn't the only factor that determines costs.
What the major factor determining cost is total manhours required.
Any uncertainties generally cause large increases in cost- esp when dealing with large bureaucracies and esp in they are second guessed by a Congress.

"Lunar requires development of a lander/return vehicle"
Not a big ticket item- total development and production could cost less than 50 million per unit
"Development of a rover"
What rover? Anyways, far less than a lander.

"R&D is not cheap these days - guess what Boeing spends on a new airplane"

I don't really know off hand- depends on plane. I just read that Gulfstream sold 3 business jets for around 60 million each to Israel.
There are a lot of factors which are critical in development costs- units production per year, how complex, how much time to build each unit, etc.

"NEO could use a modified ISS module with lots of extra consumables, no fancy recycling - KISS"
First you need to find this NEO and then decide this is the one you want to spend billions in order to go to. Next it (or they) will have a launch window, when is this? Once you have a couple of NEOs that are selected, then we can discuss a comparison cost between going to them or the Moon. My guess is the Moon will be cheaper.

"BOTH missions could add living space via inflatables"
Yes, probably.
"Lunar missions beyond 14 days require a TBD power source"
Ok, first this would be to lunar poles, so you could probably fairly easily get 20 days of sunlight. And you wouldn't really need more than say 10 days on surface. If requirement to have more than 20 days, then you could go to another location in polar region few hundred miles away which would then give you another 2 weeks or so.

"Both missions would greatly benifit from nukes as a power source and as a propulsive mechanism, especially Lunar for power (night) and the NEO for propulsion (quicker trip times)"

True. But not needed for NASA 5 billion Manned mission to lunar poles.
-gb